Tuning Twins

bsmith said:
Whynot try it without the spool flange?
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I dId at first.
Then when I torched an injector tip off and sent them all off to be rebuilt into huge conventional injectors, I dicided to pull the primary out, port the housing to accept the qsv, and try it.
If I don't like it, I can just either pull the qsv out now, or unhook the arm, and wire it in the open position.

Right now, it helps bring the primary in at a lower rpm. And it starts to open up at 8 psi from the primary.

With or without the qsv, the pressure still ends up with 50psi drive, to only 20psi out of the primary...I don't think that is good, but what do I know?
 
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Extended Power said:
I dId at first.
Then when I torched an injector tip off and sent them all off to be rebuilt into huge conventional injectors, I dicided to pull the primary out, port the housing to accept the qsv, and try it.
If I don't like it, I can just either pull the qsv out now, or unhook the arm, and wire it in the open position.

Right now, it helps bring the primary in at a lower rpm. And it starts to open up at 8 psi from the primary.

With or without the qsv, the pressure still ends up with 50psi drive, to only 20psi out of the primary...I don't think that is good, but what do I know?
Click to expand...
Gotcha. When does the qsv open?
 
Extended Power said:
I dId at first.
Then when I torched an injector tip off and sent them all off to be rebuilt into huge conventional injectors, I dicided to pull the primary out, port the housing to accept the qsv, and try it.
If I don't like it, I can just either pull the qsv out now, or unhook the arm, and wire it in the open position.

Right now, it helps bring the primary in at a lower rpm. And it starts to open up at 8 psi from the primary.
With or without the qsv, the pressure still ends up with 50psi drive, to only 20psi out of the primary...I don't think that is good, but what do I know?
Click to expand...

Here...:hehe:
 
rlawless said:
This is how I made the above spreadsheet above. Take three gauges (Over All Boost, Primary Boost & Drive Pressure.. Go for a drive and record (Take Video) of all three gauges at the same time while making several similar hard acceleration runs from zero boost to max boost, but start out the same every time.. You need my excel spread sheet to record the pressures.. Send me your email address and I'll send it to you.. Play back the video of your gauges and pause the video at every 2lbs and record to the spreadsheet... You can see exactly what is going on between chargers and when the gate is opening and maxed out... You can also tune the same way.. Cave man data recording if you will.. But the chart shows you whats happening..

I don't think your gate is opening by the boost numbers your showing above..
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I did video them...thats how I got the numbers. I just find it impossible to hold the camera steady enough while trying to keep the truck on the road.:hehe:

I think I got your e-mail already, but never ran the numbers. But I will sent it to you again, just in case.
-I wanted a quick answer, and confirmation that the primary needed to be kicked in the ass sa more. (I'm sorry for being lazy today.):bang
 
Alrighty...changed tunes in the truck to see if we could reduce the smoke a little bit at idle. (this tune is for the injectors I have now)
Did not adjust the spring gate, as I wanted to see if anything changed as far as pressures go.
Drive pressure to the secondary had the needle straight down. (guessing 110+psi)
Drive pressure to the primary was 52psi
Boost out of primary was only 15psi.
Total boost dropped off to 50psi.

Pulled over and backed the spring pressure off a couple turns.
Resulted in:
100psi drive pressure to secondary.
40-45psi to the primary.(it was bouncing, so I think the gate was starting to open)
20psi out of the primary.
65 psi total boost to the engine.
STILL can't get over 20psi out of the big charger.

Pulled over, and backed the gate off a little too much, as the Allen wrench shot past my left ear with a "twinggggg!" and landed somewhere in the ditch of 3 foot high grass...never to be seen again..

So...I thought this would be a good time to see what the drive pressure would be knowing that the gate ports were as open as open could ever be...
The results:

80psi drive to the secondary.
42psi to the primary.
20psi out of the primary.
And only 40psi total boost..

That is what I could see on the video before the truck was trying to pull an abrupt u turn, and I had to back out of it completely.

Trying to drive home with the waste gate open sucked ass, as it was a hot, smokey, laggy b!tch. I had to use the tow haul light to keep the revs up.

On the highway, at 75mph, with the spring Gate actuator connected, I usually had 10psi total boost to the engine.
With the waste gate actuator disconnected completely, I had FA.

I gotta ask...what does it sound like when the waste gate opens?
I had a sound...the last time I heard it...It was the turbo imploding on itself in the turbine housing.
It also sounds a little like a torn boot...but I haven't found that yet...

So I am waiting for the turbos to cool off. (huge fan on top of the engine) and will pull the piping to see if one of the turbos took a dump.
 
Both turbos are ok.
Changing out the waste gate spring with the other spring I have won't work cuz it is very tight, and will prolly just bind up all the time.
So, I had to pull the whole spring style waste gate actuator off, and put the other one on instead.
Now I can't get the circlip back on. (gonna have to pull the charger to install the stupid little clip.)

Found the cause of the sound...apparently 110+psi is the point the up pipes start to leak at the manifold joints.

Nuff...I'm going to bed.
 
Extended Power said:
I did video them...thats how I got the numbers. I just find it impossible to hold the camera steady enough while trying to keep the truck on the road.:hehe:
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I use my cell phone (Droid Razr) its does a good job.. I wish I had a mount though.. I hear ya about driving and recording at the same time, it gets a bit hairy..

40 total boost & 20 primary = Primary 75% & 33% secondary is better than before..

You didn't put your email address in the PM you sent me..
 
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SHughes said:
A couple guys here have tried it. It doesn't work as well in practice as it does in theory. I don't believe anyone has continued to use such a set-up.
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Yeah it doesn't work cuz the WG spring has to be set fairly light and then DP pushes it open or creeps.. I know on the OEM WG if loosened up enough to just slide onto the gate lever (no tension) the gate opens at 18lbs..

I'm now using AFE's new WG actuator W/a 40lb. spring and it has made a big improvement when bringing the primary on line.. Its very consistent and smooth with no creep..
 
When you say it opens at 40 psi, are you just referencing the drive pressure, and then actuating the pod with a solenoid?
 
The math that is posted is odd to me in many ways, I've run (not currently) over the years a few twin setups and my data is a bit different. The setup in my avatar is an HX-40-16/ HT3B-26 with a divorced gate setup using the internal gate (like the old Piers twin setup) it was running at 60 psi total with the 3B making 33-35 psi and drive pressure at 65......just info for you!

Jim
 
Extended Power said:
When you say it opens at 40 psi, are you just referencing the drive pressure, and then actuating the pod with a solenoid?
Click to expand...

Forget about DP.. Boost opens the gate and is used to tune the proficiency of the turbos.. DP is the result of the turbos size, settings.. small exhaust housings cause most high DP but so does over fueling to say the least..

The post above this states only 65 psi of DP, but his exhaust housing is 16cm (larger).

Sent from my DROID RAZR using Tapatalk 2
 
Jim Fulmer said:
The math that is posted is odd to me in many ways, I've run (not currently) over the years a few twin setups and my data is a bit different. The setup in my avatar is an HX-40-16/ HT3B-26 with a divorced gate setup using the internal gate (like the old Piers twin setup) it was running at 60 psi total with the 3B making 33-35 psi and drive pressure at 65......just info for you!

Jim
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I'm running that same turbos you are and seeing the same results. I just dont have a drive reassure gauge. What rpm does your turbos start to build boost.
 
Just verified all pressure gauges. (Not that the primaries output gauge only goes to 20 psi and stays there.)
-all within .5 psi of test gauge.
-Cleaned both particle filters. The filter on the secondary was wet with water, and blown through.
-New spring gate actuator installed with lighter spring.
-just finishing up the piping and tighten up the exhaust up pipe, and I'm back in business again.
 
I have a chance to buy an .80 open T4 housing for my 68mm turbine.

When the waste gates were open because the spring gate became unsparing, it was a complete laggy sob.

Do you think a .70 divided T3 waste gated housing with the .620" ports in the completely open position would be the same response as an open T4 .80? (as far as bottom end spool up)
 
Extended Power said:
I have a chance to buy an .80 open T4 housing for my 68mm turbine.

When the waste gates were open because the spring gate became unsparing, it was a complete laggy sob.

Do you think a .70 divided T3 waste gated housing with the .620" ports in the completely open position would be the same response as an open T4 .80? (as far as bottom end spool up)
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From the consenus of the board, stay away from a open housing on secondary.

It will slow spool.
 
So now what?
With the gates open all the time on this .70...with the ports opened up to .620" it was a dog off the line...almost to the point of being undrivable because of the heat and smoke.
And then when I floored it...the drive pressure was still 80 psi.

I can honestly say that the best it ran was with the stiff spring in the actuator, even though the primary was only able to put out 20 psi, and 65 total boost.

Not sure if changing turbine housing to an .80 would help much. Almost like I need a bigger exhaust wheel or what?
 
Extended Power said:
So now what?
With the gates open all the time on this .70...with the ports opened up to .620" it was a dog off the line...almost to the point of being undrivable because of the heat and smoke.
And then when I floored it...the drive pressure was still 80 psi.

I can honestly say that the best it ran was with the stiff spring in the actuator, even though the primary was only able to put out 20 psi, and 65 total boost.

Not sure if changing turbine housing to an .80 would help much. Almost like I need a bigger exhaust wheel or what?
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Why do you want your gates open all the time?

Also the 65psi total boost and 20psi primary boost seems pretty good.
 
Headcase98002 said:
Why do you want your gates open all the time?

Also the 65psi total boost and 20psi primary boost seems pretty good.
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I don't. When I backed the spring off too much when I was trying to get the gate to open, the spring bolt came undone, and there was no way for me to hook it back up...so, it was a great time to see what the drive pressure would be with the gates totally open with the .70 housing.

Now I know, that even when the gates are 100% open, I will still have 80 psi drive pressure to the secondary.
 
Extended Power said:
Ok so here's my set up:

Ford 6.0L with 285cc/150% injectors.
dual hpop's

ED. billet 63/68/.70 (12cm) over a FI S482/92/1.10
The secondary is wastegated with a spring style actuator. (Which I believe, the spring is too stiff)
I have a Sound Performance Quick Spoool Valve on the 82mm that starts to open at 8 psi. (referenced from the 82mm's output boost)

Cruising down the highway, 75mph, and roll into it so it doesn;t down shift, I have this:

100 psi drive pressure to the secondary. (63mm)
50-55 psi drive to the primary. (82mm)
Only got 20 psi coming out of the 82mm for boost.
Total boost pressure to engine is 65psi.

Can someone figure out the ratios for me, and what I need to do please?

I think I need either a bigger housing on the T3, so a divided .80 or even an open .80....or try a lighter spring in the wastegate actuator so it opens up sooner.

...thoughts?
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My opinion:
Since you've tested the theory that wastegates wide open still resulted in just 20 psi from S482, the turbine wheel on the S482 is not large enough to drive the compressor beyond 20 psi with your current setup. It takes pressure differential and heat to create shaft horsepower through the turbine wheel. A bigger turbine wheel would likely create more shaft horsepower and provide that extra inter-stage boost you are looking for.

A smaller top turbo would likely also create a setup where more boost pressure is generated from the S482 but that would come from two things which would probably not create more peak horsepower but possibly increase drive-ability and boost response:
1. Smaller turbo extracting less heat energy from the exhaust flow therefore more heat energy is available for the S482.
2. Smaller turbo consumes less interstage air, therefore there will be more restriction and higher boost from the S482 but likely the same overall lbs/min airflow from the S482.
 
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